Substances that contain more OH⁻ ions than H⁺ ions are most likely bases.
Explanation: In chemistry, substances are classified as acids, bases, or salts based on the ions they produce in solution. Acids are substances that release hydrogen ions (H⁺) when dissolved in water, while bases release hydroxide ions (OH⁻). Salts are formed from the neutralization reaction between an acid and a base.
When a substance has more OH⁻ ions than H⁺ ions, it means it is releasing more hydroxide ions into the solution. This characteristic is typical of bases. Bases are known for their ability to neutralize acids and often have a slippery feel and a bitter taste. Common examples of bases include sodium hydroxide (NaOH) and potassium hydroxide (KOH).
Therefore, the correct answer is b) bases.